Four common variables: Family_namein the Catasto [SURNAM1 in the Online Tratte], Name [NAME1 in the Tratte], Patronymic [NAME2 in the
Tratte], and Location [QUAR in the
Tratte] permit you to search for
individuals between the two data sets. In addition the variable Trade in the Catasto [OCSTAT in the Tratte] appears in both sets. However you must be aware of
some considerations.

1)Family_name, Name, and Patronymic have 10 letters
in the Catasto; SURNAM1, NAME1, and
NAME2 have 11 letters in the Tratte. You need to truncate one
more letter for truncated names in the Tratte when looking them up in the Catasto, and add one from the Catasto in the Tratte (or better still, check
the lists of Surnames for both data sets to find an acceptable
spelling).

2)
The spelling of names has not been standardized between the Catasto and the Tratte (which has the more authoritative
versions—there is also more information about names in the
documentation for the Tratte than for
the Catasto). You will have to guess at
matches in the spelling of names between the two data sets. A match of the Gonfalone (Location in the Catasto; QUAR in the Tratte) may help you find the right
person.

3)
Many names and patronymics are missing from the Catasto data set. This is because David Herlihy did not code the names of subordinate
family members listed in the tax declarations. For instance, the name of
Cosimo [di]
Giovanni de’ Medici is not present in the Catasto data set, although there are many
records for him in the Tratte, because
he was listed as a subordinate family member in the declaration of
his father, Giovanni [di] Bicci de’ Medici in the Catasto. Of the 37,144 individual
names that appeared in the original records of the Catasto for 1427, only 9,780 names of
household heads (and only 36% of these had surnames) appear in the
Catasto data set. Thus you will not find in
the Catasto the names of many
individuals who were living in 1427, although they may be present
in the Tratte. But you might be able to
surmise from patronymics available in the Tratte in which household an individual may
have been living in the Catasto.